RU2702297C2 - Pressure relief valve (embodiments) and valve assembly containing said valve - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: invention relates generally to pressure relief valves, in particular, to pressure release valves for steam fuel systems. Pressure release valve (10) is designed to control the fluid flow between the first fluid passage (12a) and the second fluid passage (12b). Pressure relief valve comprises housing (14), diaphragm element (24) movably fixed inside housing and having hole (18) for fluid medium, first deflecting element (20) for forced movement of diaphragm element in first direction and sealing element (26) movably installed in housing and made with possibility of reversible sealing of hole (18) for fluid medium. When pressure in second fluid passage (12b) exceeds first predetermined threshold value, diaphragm element (24) is pressed to first diverting element (20), and sealing element (26) is first forced to move to fluid medium opening (18) and then comes out of contact with fluid medium opening, providing fluid communication between the second fluid passageway (12b) and the first fluid passageway (12a) by means of a fluid hole. When pressure in second channel (12b) for fluid medium decreases below second predetermined threshold value, sealing element (26) comes out of contact with diaphragm element (24), providing fluid communication between the first fluid passage and the second fluid passage by means of a fluid port. Also provided is a valve assembly comprising a pressure release valve (10) and valve (60) driven from outside.

EFFECT: technical result is elimination of insufficient pressure, as well as delay of valve release at excess pressure, wherein each of these actions begins from initial closed position, wherein as soon as the sealing element stops interacting with the diaphragm element under insufficient pressure conditions, this allows the fluid medium to flow from the first hole to the second hole through the fluid medium hole.

28 cl, 5 dwg

Description

FIELD OF TECHNOLOGY

The present invention relates generally to pressure relief valves, and in particular to pressure relief valves for steam fuel systems.

BACKGROUND OF THE INVENTION

Pressure relief valves are well known and are commonly used in fuel systems to open at a predetermined pressure difference in the valve until the pressure difference decreases to a predetermined level. For example, such valves allow fuel vapors to be removed from the fuel tank with an unacceptable increase in pressure in the fuel tank above the ambient pressure level.

Typically, such valves comprise a valve element configured to reversibly form a seal with a valve seat, a sensing element, such as a diaphragm or piston, on which it is necessary to adjust the pressure difference, and an element for applying a reference force, for example a spring, which sets the pressure difference at which the valve should open.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provided a pressure relief valve for controlling a fluid flow between a first fluid passage and a second fluid passage, the pressure relief valve comprising:

a housing comprising a first opening associated with said first fluid channel and a second opening associated with said second fluid channel, the housing defining a mechanical stop;

a diaphragm element movably fixed inside the housing and defining a hole for the fluid to selectively provide through it fluid communication between the first channel for the fluid and the second channel for the fluid;

a first deflecting element provided in said first fluid channel and configured to forcibly move said diaphragm element to said mechanical stop in a first direction; and

a sealing element provided in said second fluid channel and movably mounted in said housing and comprising a sealing surface configured to reversibly seal said fluid hole, said sealing element comprising a second deflecting element configured to forcibly move said sealing surface to the specified hole for the fluid in the second direction, and moreover, the movement of the specified seal the element in the specified second direction is limited.

In particular, in response to the first pressure in the second fluid passage exceeding the first predetermined threshold value, said diaphragm element is pressed against said first deflecting element and said sealing element is forcedly moved to said fluid hole until the locking element is restricts its movement, whereby the sealing surface then comes out of contact with the specified hole for the fluid, providing a fluid connection between a second fluid channel and a first fluid channel through said fluid hole. In addition, in response to a decrease in the second pressure in the second fluid channel below the second predetermined threshold value, said sealing element is pressed against said second deflecting element, while said diaphragm element is pressed against said mechanical stop, whereby said sealing surface comes out out of contact with the diaphragm element, providing fluid communication between the first fluid channel and the second fluid channel by om said opening for a fluid. For example, said first direction is opposite to said second direction.

As a complement or alternative, for example, the diaphragm element comprises a central part and a peripheral part, the diaphragm element being attached inside the specified housing using the specified peripheral part, and moreover, the specified hole for the fluid is located in the specified Central part. For example, said central portion is capable of reversibly moving relative to said peripheral portion at least in said first direction.

As a complement or alternative, for example, the valve further comprises a piston element located between said first deflecting element and said diaphragm element, said piston element having a lumen exactly corresponding to said fluid opening.

As a complement or alternative, for example, said mechanical stopper has the shape of a cylindrical wall protruding into the housing from one end of the housing and comprising an edge configured so as to abut reversibly abut against said diaphragm element. For example, said sealing element is placed inside said cylindrical wall. For example, said cylindrical wall comprises locking elements for restricting movement of said sealing element in a direction opposite to said second direction.

As a supplement or alternative, for example, said sealing element comprises a locking element adapted to limit said movement of said sealing element in said second direction. As a supplement or alternative, for example, said sealing element is maintained in sealing contact with the diaphragm element by means of a second deflecting element until the movement of said sealing element relative to said housing is stopped by said locking element.

As a supplement or alternative, for example, said diaphragm element is able to move away from the sealing element and come out of contact with it after the movement of said sealing element relative to said housing is stopped by said locking element.

As a complement or alternative, for example, said first deflecting member is a first mechanical spring.

As a complement or alternative, for example, said second deflecting member is a second mechanical spring.

As a complement or alternative, for example, said first predetermined threshold value corresponds to the presence of increased pressure in the second fluid channel compared to the first fluid channel.

As a supplement or alternative, for example, said second predetermined threshold value corresponds to the presence of a reduced pressure in the second fluid channel compared to the first fluid channel.

As a complement or alternative, for example, said first deflecting member, said diaphragm member, and said sealing member are arranged in series and aligned along an axis relative to said housing.

As a complement or alternative, for example, said first deflecting member, said diaphragm member, said sealing member and said second deflecting member are arranged in series and aligned along an axis relative to said housing.

As an addition or alternative, for example, said first deflecting element, said diaphragm element, said sealing element, said second deflecting element, and said cylindrical wall are arranged in series and aligned along an axis relative to said housing.

As a complement or alternative, for example, in response to an increase in pressure in the second fluid channel above a third predetermined threshold value that is smaller than said first predetermined threshold value, said diaphragm element is pressed against said first deflecting element and forced movement of said sealing element is supported. to the specified hole for the fluid, and the specified third predetermined threshold value is not sufficient for displacements of the sealing element so that the locking element is restricted its movement, whereby the sealing surface continues to hermetically close said opening of the fluid, preventing fluid communication between the second fluid channel and a first fluid channel through said opening for a fluid.

As a complement or alternative, for example, said first fluid passage provides fluid communication between the first reservoir and said pressure relief valve, wherein the second fluid passage provides fluid communication between the pressure relief valve and the second reservoir. For example, said first reservoir comprises a vapor treatment device and / or said second reservoir comprises a fuel tank.

According to another aspect of the present invention, there is provided a valve assembly comprising a first pipe connected to a fuel vapor processing device and a second pipe connected to a fuel tank, the valve assembly comprising:

a pressure relief valve as defined in accordance with a first aspect of the present invention;

externally actuated valve; and

a connecting element comprising a main part comprising a first pipe connected to a fuel vapor processing device, a second pipe connected to a fuel tank, and comprising a first socket for receiving a pressure relief valve therein, and a second socket for holding a valve operable therein from the outside. For example, said first conduit defines a main opening and an overflow opening, wherein said overflow opening is in fluid communication with a first fluid passage defined by a pressure relief valve body.

As a complement or alternative, the second conduit is in fluid communication with the second fluid conduit.

As a complement or alternative, an externally actuated valve is located in said second fluid channel and is actuated to selectively open or close fluid communication between the tank and the fuel vapor treatment device through said main opening.

As a supplement or alternative, for example, said valve, actuated externally, is configured to be actuated by an external energy source. For example, said valve, actuated externally, is an electromechanical valve. For example, said valve, actuated externally, contains a solenoid containing an armature that selectively extends from the main part of the solenoid and slides into it, and a plunger mounted on said armature and configured to seal contact with said main hole. For example, said valve, actuated externally, is a solenoid valve actuated by electricity.

As a supplement or alternative, for example, said valve, actuated externally, is configured to be pulsed by a controller, thereby allowing an intermittent fluid flow to pass through its main opening located between said first conduit and said second conduit.

According to another aspect of the present invention, there is provided a pressure relief valve for controlling a fluid flow between a first fluid passage and a second fluid passage. The pressure relief valve comprises a housing, a diaphragm element movably fixed inside the housing and containing a hole for the fluid, a first deflecting element for forcing the diaphragm element to be moved in the first direction, and a sealing element movably mounted in the housing and configured to reversibly seal the fluid hole . When the pressure in the second fluid channel exceeds a first predetermined threshold, the diaphragm element is pressed against the first deflecting element, and the sealing element is first forced to move to the fluid hole and then out of contact with the fluid hole, providing fluid communication between a second fluid passageway and a first fluid passageway through the fluid hole. When the pressure in the second fluid passage decreases below the second predetermined threshold value, the sealing element comes out of contact with the diaphragm element, providing fluid communication between the first fluid passage and the second fluid passage through the fluid opening. Also provided is a valve assembly comprising a pressure relief valve and an externally actuated valve.

According to another aspect of the present invention, there is provided a pressure relief valve for controlling a fluid flow between a first fluid passage and a second fluid passage. The pressure relief valve comprises a piston element defining a hole for the fluid passing therethrough between the first channel for the fluid and the second channel for the fluid, and comprises a first deflecting element configured to force the said piston element to move to the wall. The pressure relief valve further comprises a sealing element comprising a sealing surface configured to seal said fluid hole, said sealing element comprising a second deflecting element configured to forcibly move said sealing surface to said hole and further comprising a locking element made with the possibility of restricting the movement of the specified sealing element to the specified item rshnevomu element.

According to at least one example of this aspect of the present invention, the pressure relief valve is configured such that when the pressure in the second fluid passage exceeds a predetermined threshold value, a pushing action is opposed to said piston element to counteract the forces of said first deflecting element and said seal the element is forced to move to the hole of the specified piston element until the locking element limits its movement, whereby the sealing surface comes out of contact with the hole, allowing fluid flow to pass between the second fluid channel and the first fluid channel, and when the pressure in the second fluid channel falls below a predetermined threshold value, said sealing element is forced to move, counteracting the efforts of the specified second deflecting element, while the specified hole is forcibly moved to the specified wall, whereby the specified seal itelnaya surface out of contact with the opening, allowing fluid flow to pass between the first fluid channel and a second channel for a fluid.

Any number of the following features and structures may be implemented in a pressure relief valve according to at least one example of the present invention, individually or in combination with each other:

- The first deflecting element may be a main spring, while the second deflecting element may be an auxiliary spring, and the main spring exerts forces exceeding the forces exerted by the auxiliary spring.

- The wall may be a cylindrical wall containing a first edge defining an internal channel.

- The piston element may further comprise a diaphragm attached to it and having a window located on the same axis with the hole.

- The locking element may be a pair of levers passing under the sealing surface, each of which has a lateral protrusion made with the possibility of contact with the second wall inside the valve, thereby restricting the movement of the sealing element to the piston element.

- The second wall may be a side wall extending from the second edge of the cylindrical wall.

According to an additional aspect of the present invention, there is provided a pressure relief valve comprising a main part comprising a first pipe connected to a first tank and a second pipe connected to a second tank open to the atmosphere and an externally actuated valve located in said body with the possibility of pulsed actuation by the controller, thereby allowing an intermittent fluid flow to pass between said first reservoir and said second m tank. The main part further comprises a socket for holding a housing defining a first fluid channel in fluid communication with the first pipe, and a second fluid channel in fluid communication with the second pipe. The housing contains a piston element defining a hole for the fluid passing therein between the first channel for the fluid and the second channel for the fluid, and contains the first deflecting element configured to force the specified piston element to the wall. The housing further comprises a sealing element comprising a sealing surface adapted to seal said fluid hole, said sealing element comprising a second deflecting element configured to forcely move said sealing surface to said hole and further comprising a locking element configured to restrictions on the movement of the specified sealing element to the specified piston element that one.

The pressure relief valve is designed so that the valve, actuated from the outside, is configured to open, thereby relieving pressure from the second tank. The pressure relief valve is additionally designed so that when the pressure in the second reservoir exceeds a predetermined threshold value, the said piston element has a pushing effect that counteracts the forces of the specified first deflecting element, and the specified sealing element is forced to move to the hole of the specified piston element until the locking element does not limit its movement, whereby the sealing surface comes out of contact with the hole allowing fluid flow to pass between the second tank and the first tank, and when the pressure in the second tank drops below a predetermined threshold value, said sealing element is forced to move, counteracting the forces of said second deflecting element, while said hole is forcibly moved to said wall, wherein said sealing surface is out of contact with the hole, allowing fluid flow to pass between the first reservoir rum and a second tank.

BRIEF DESCRIPTION OF GRAPHIC MATERIALS

In order to provide a better understanding of the present invention disclosed herein and as a good example of its practical implementation, examples will now be described as non-limiting examples with reference to the accompanying drawings, in which:

in FIG. 1 is a sectional side view of a pressure relief valve according to one example of the present invention when closed;

in FIG. 2 is a sectional side view of the pressure relief valve of FIG. 1 in a partially open state at elevated pressure;

in FIG. 3 is a sectional side view of the pressure relief valve of FIG. 1 in the open state at elevated pressure;

in FIG. 4 is a sectional side view of the pressure relief valve of FIG. 1 in the open state under reduced pressure;

in FIG. 5A is an exploded isometric view of a main body of a valve comprising a pressure relief valve of FIG. 1, integrated into it; in FIG. 5B is a sectional side view of the main part of the valve of FIG. 5A comprising an externally actuated valve installed therein.

DETAILED DESCRIPTION

As shown in FIG. 1-4, the pressure relief valve according to the first example of the present invention is generally indicated by 10, and operates to selectively control a fluid flow, i.e., fluid communication, between the first fluid passage 12a and the second passage 12b for fluid. As will be described in more detail below, the pressure relief valve 10 includes a housing 14 accommodating a diaphragm element 24 having a window 25 that acts as a fluid opening 18. The fluid hole 18 is configured to provide selective fluid communication between the first fluid passage 12a, which may include an inlet formed in the housing 14, and the second fluid passage 12b. The diaphragm element 24 essentially divides the housing 14 into a first housing portion 14a comprising at least a portion of a first fluid passage 12a and a second housing portion 14b comprising at least a portion of a second fluid passage 12b.

The first fluid passage 12a provides fluid communication between the first reservoir, for example a vapor treatment device (also referred to herein as a “canister”), and a pressure relief valve 10 (in particular, its first housing part 14a), while as the second fluid passage 12b provides fluid communication between the pressure relief valve 10 (in particular, its second housing part 14b) and a second reservoir, such as a fuel tank.

The first housing portion 14a is configured to selectively deflect the diaphragm element 24 toward a mechanical stop located in the second housing portion 14b. A mechanical stop is also referred to herein by the equivalent term “wall”, and is defined in this example by the first edge 22a of the cylindrical wall 22. To this end, the first deflecting element, shown here as the main mechanical spring 20, is configured to force the diaphragm element 24 to the wall, i.e. to the first edge 22a, and with the possibility of forming an abutment with the wall 22. To facilitate such a forced movement, the piston element 16 is displaced in the first housing part 14a and the first deflecting element, in this example the main spring 20, forces the piston element 16 to the diaphragm element 24, and thereby forcibly moves the diaphragm element 24 to the wall defined inside the second housing part 14b. In alternative embodiments of this example, the piston element 16 may be replaced by a disk, plate or ring, for example, or instead may be eliminated, then the first deflecting element or spring 20 directly abuts against the diaphragm element 24.

In this example, the piston element 16 defines a lumen 17, exactly corresponding to the window 25, and thus exactly corresponding to the hole 18 for the fluid.

As mentioned above, the mechanical stop for the diaphragm element 24 is provided by a wall, which according to the present example is a cylindrical wall 22 containing a first edge 22a defining an inner channel 23a. The cylindrical wall 22 is located inside the second part 14b of the casing so that the outer channel 23b is defined between the cylindrical wall 22 and the casing 14, in particular between the cylindrical wall 22 and the second part 14b of the casing.

The cylindrical wall 22 is located inside the housing on the same axis with the diaphragm element 24, and thus also on the same axis with the piston element 16 in this example, so that when the diaphragm element 24 abuts the first edge 22a of the wall 22, the flow of fluid between the inner channel 23a and the outer channel 23b.

According to the depicted example, the diaphragm element 24 is movably fixed inside the housing 14. In particular, the diaphragm element 24 comprises a peripheral part 24a connected to the central part 24b by means of an annular part 24 s. The peripheral part 24a is fixedly attached to the housing 14, and the central part 24b is able to move relative to the peripheral part 24a (by means of the annular part 24c) and, thus, relative to the housing 14. Thus, the diaphragm element 24, by means of the central part 24b, is capable of reversibly moving along axis inside the housing 14, i.e. in the directions back and forth. The window 25, and thus the fluid hole 18, is located in the central portion 24b.

The diaphragm element 24 selectively enables or prevents the passage of a fluid stream, i.e., fluid communication, between the first fluid passage 12a and the second fluid passage 12b. In order to allow the diaphragm element 24 to alternately move away from and to the wall 22, while its outer periphery is attached to the housing 14, the diaphragm element 24 is flexible, at least along the annular part 24c between the outer peripheral part 24a and the Central part 24b , which rests on the piston element 16.

The pressure relief valve 10 further comprises a sealing element 26, also referred to herein by the equivalent term “closing element”, and comprising a sealing surface 28 configured to seal the fluid hole 18 in contact with it. The sealing element 26 is movably mounted in the housing 14, and in particular is housed inside the cylindrical wall 22. According to the present example, the sealing surface 28 comes into contact with the part of the diaphragm element 24 surrounding the hole 18, thus the diaphragm element 24 and the sealing surface 28 are made of one or several materials with appropriate sealing properties. The sealing properties of the diaphragm element 24 and the sealing surface 28 can be determined according to the characteristics of the fluid that must pass through the pressure relief valve 10, the range of pressure levels and the medium in which the pressure relief valve 10 is intended to be used. For example, if a pressure relief valve 10 is used to control the pressure in a steam fuel system, for example, in a vehicle fuel system, the sealing properties should be selected so as to withstand the normal pressure level in the fuel tank, as well as the chemical properties of the fuel.

The sealing element 26 contains a second deflecting element, shown here in the form of an auxiliary mechanical spring 30, configured to force the sealing surface 28 to move to the hole 18. The sealing element 26 further comprises a locking element, shown here in the form of a pair of levers 32 extending under the sealing surface 28 , each of which has a lateral protrusion 34 made with the possibility of contact with the second wall inside the pressure relief valve 10, thereby limiting the displacements of the sealing element 26 to the diaphragm member 24.

According to the illustrated example, the second wall is a side wall 36 extending inwardly from the second edge 22b of the cylindrical wall 22 to the inner channel 23a. Thus, the cylindrical wall 22 defines the inner channel 23a as extending between the second edge 22b and the side wall 36 at its first edge, and is configured to accommodate the sealing member 26 and to allow it to move forward and backward inside the inner channel 23a. The sealing element 26 is located inside the inner channel 23a so that the sealing surface 28 is located at or near the first edge 22a, and the side protrusion 34 is located outside the inner channel 23a in close proximity to the side wall 36.

Accordingly, for the position range of the diaphragm element 24, including the positions depicted in FIG. 1 and FIG. 2, the forward displacement of the sealing element 26 relative to the second housing element 14b causes the sealing surface 28 to contact the diaphragm element 24, thereby sealing the opening 18. In addition, and as shown in FIG. 4, the rearward displacement of the sealing element 26 is relative to the second housing element 14b leads to the separation of the sealing surface 28 and the diaphragm element 24, thereby ensuring the passage of fluid flow through the hole 18. However, the displacement of the sealing element 26 forward d along the axis is limited by contact of the lateral projection 34 positioned outside the inner channel 23a, with the side wall 36, the purpose of which is explained hereinafter. Similarly, the rearward displacement of the sealing element 26 along the axis is limited by the locking element, which in this example has the shape of an inclined part 27 defined on the inner surface of the cylindrical wall 22. The inclined part 27 may have a diameter that is smaller than the diameter of the sealing surface 28, thereby limiting the displacement the sealing element 26. In alternative embodiments of this example, the inclined portion can be replaced with a suitable radial protrusion, for example, to provide a stopper function.

The side wall 36 may extend inward from the entire circumference of the cylindrical wall 22, restricting the movement of the levers 32 by contact with the side protrusion 34. Alternatively, the side wall 36 may extend from parts of the cylindrical wall 22, for example, parts corresponding to the position of the side protrusion 34.

According to the present example, the sealing element 26 is deflected forward, and for this purpose, the second deflecting element, in this example having the form of an auxiliary spring 30, is located inside the inner channel 23a and is designed so as to abut against the inner surface of the side wall 36 so as to force move the sealing element 26 to the diaphragm element 24. The auxiliary spring 30 is arranged to force the sealing element 26 to seal the opening 18 d the moment when the pressure difference between the pressure level in the second channel 12b and the fluid pressure level in the first channel 12a of the fluid drops below a predetermined threshold value.

In the illustrated example, the main spring 20, forcibly moving the diaphragm element 24 to the cylindrical wall 22, exerts forces on it exceeding the forces exerted on the sealing element 26 by the auxiliary spring 30. As a result, and as explained later in the present description, the pressure level required for opening the hole 18 in spite of the action of the first deflecting element, i.e., by counteracting the main spring 20, to thereby displace the diaphragm element 24 back above the level of pressure required to tearing of the hole 18 by withdrawing the sealing element 26 in spite of the action of the second deflecting element, that is, the auxiliary spring 30. Due to the fact that the direction of the forces exerted by the main spring 20 is opposite to the direction of the forces exerted by the auxiliary spring 30, the diaphragm element 24 may be used to adjust the overpressure that may be present in the second fluid passage 12b, while the sealing element 26 may be used to adjust the underpressure to ond may be present in the second channel 12b to the fluid.

Under normal operating conditions, the valve 10 is in the closed position, as shown in FIG. 1, the diaphragm element 24 being forced forward by the main spring 20 by means of the piston element 16 so that the central part 24b of the diaphragm element 24, near the hole 18, abuts against the first edge 22a of the cylindrical wall 22, preventing the passage of fluid flow between the external channel 23b and the inner channel 23a. In this position, the sealing element 26 is simultaneously forced forward by the auxiliary spring 30 so that the sealing surface 28 abuts against the diaphragm element 24, in particular its central part 24b, which closes the window 25 therein, and, as a result, hermetically closes the hole 18. Since, as described above in this text, the direction of the forces exerted by the main spring 20 is opposite to the direction of the forces exerted by the auxiliary spring 30, in this closed position on the sealing element 26 and the diaphragm the rag element 24 is pushed towards each other, thereby maintaining a tightly closed state of the hole 18 and preventing fluid communication between the first fluid passage 12a and the second fluid passage 12b.

It should be understood that at this point, the increasing pressure in the second fluid passage 12b (as compared to the pressure in the first fluid passage 12a) also forces the sealing element 26 toward the diaphragm element 24, thereby providing better contact with it and preventing leakage fluid through the hole 18. As explained below, only when the pressure difference between the pressure in the second fluid channel 12b and the pressure in the first fluid channel 12a overcomes the efforts of the main spring 20, the hole 18 opens. Accordingly, the valve 10 provides a variable sealing contact between the diaphragm element 24 and the sealing surface 28 for tightly closing the hole 18, depending on the pressure difference between the second fluid passage 12b and the first fluid passage 12a. Thus, at normal pressure, the sealing surface 28 and the diaphragm element 24 can be held in a closed position with less force applied thereto, thereby preventing damage to them.

The following is a reference to FIG. 2. When the pressure difference between the second fluid passage 12b and the first fluid passage 12a rises to a predetermined threshold, that is, to a value where the forces exerted on the diaphragm element 24 are greater than the forces exerted by the main spring 20, the diaphragm element 24, in particular its central portion 24b, moves slightly backward from the first edge 22a of the cylindrical wall 22. The pressure differential between the sides of the hole 18 continues to force the sealing element 26 forward, thus keeping the sealing contact with the diaphragm element 24 and maintaining the closed position of the hole 18. The sealing element 26 can freely move forward until the lateral protrusion 34 of the levers 32 comes into contact with the side wall 36 at the second edge 22b of the cylindrical wall 22. Thus , the length of the levers 32 and the cylindrical wall 22 determines the distance by which the sealing element 26 follows the diaphragm element 24 and maintains the closed state of the hole 18.

In this position, since the diaphragm element 24 comes out of contact with the first edge 22a of the cylindrical wall 22, a fluid may pass between the external channel 23b and the internal channel 23a.

As shown in FIG. 3, as the pressure difference between the second fluid passage 12b and the first fluid passage 12a further increases to another predetermined threshold, the diaphragm element 24, in particular its central portion 24b, is further offset back from the first edge 22a of the cylindrical wall 22 to its retracted position. However, at this moment, the sealing element 26 is held by the contact of the side wall 36 and the lateral protrusion 34 of the levers 32, which prevents its further forward movement. As a result, the sealing surface 28 of the sealing element 26 comes out of contact with the diaphragm element 24, thereby allowing the flow of fluid to pass between the first fluid channel 12a and the second fluid channel 12b through the hole 18. The diaphragm element 24, in particular its central part 24b, is maintained in a retracted position until the pressure drop on both sides of the hole 18 becomes less than the forces exerted by the main spring 20 on the diaphragm element 24, in particular on its central the second part 24b.

Next, consider FIG. 4, which depicts a negative pressure drop at which the pressure level in the second fluid channel 12b is lower than the pressure level in the first fluid channel 12a, and the diaphragm element 24 is forced to move to the first edge 22a of the cylindrical wall 22, thereby preventing the passage of flow fluid between the external channel 23b and the internal channel 23a. As the pressure difference between the pressure level in the second fluid channel 12b and the pressure level in the first fluid channel 12a falls below another predetermined threshold at which the negative pressure drop overcomes the forces exerted by the auxiliary spring 30, the sealing element 26 retracts, thereby coming out of contact with the diaphragm element 24, in particular with its Central part 24b. As a result, the orifice 18 opens, thereby allowing the flow of fluid to pass between the first fluid passage 12a and the second fluid passage 12b. It should be noted that according to the illustrated example, under reduced pressure (for example, in the case of the aforementioned negative pressure drop), since the sealing element 26 is retracted backward, this facilitates the passage of the fluid flow only through the internal channel 23a, in contrast to the high pressure conditions, under of which the piston element 16 moves forward, thereby facilitating the passage of the fluid flow both through the internal channel 23a and through the external channel 23b.

It should be noted that according to the present invention, a common orifice, i.e., a fluid orifice 18, is used to adjust the increased pressure or reduced pressure in the second fluid passage 12b compared to the pressure in the first fluid passage 12a, such thereby reducing valve manufacturing costs in at least some examples of the present invention. In addition, the risk of valve failure can also be reduced in at least some examples of the present invention.

It should also be noted that although in this example a single fluid port 18 provides selective fluid communication between the second fluid port 12b and the first fluid port 12a, in alternative embodiments of this example, the single fluid port can be replaced with multiple windows in the diaphragm element and / or in the piston element 16, and all such windows simultaneously open or close selectively by means of a sealing element 26. It should also be noted that in In the example, the first deflecting element 20, the diaphragm element 24, the sealing element 26, the specified second deflecting element 30 and the cylindrical wall 22 are arranged in series and aligned along the axis relative to the specified housing 14. However, other arrangements are possible: for example, the first deflecting element 20, the diaphragm element 24, the sealing element 26 are arranged sequentially and aligned along the axis relative to the specified housing 14; or the first deflecting element 20, the diaphragm element 24, the sealing element 26, the specified second deflecting element 30 are arranged in series and aligned along the axis relative to the specified housing 14.

As shown in FIG. 5A and 5B, according to one example of the present invention, the pressure relief valve 10 can be used in conjunction with an externally actuated valve, indicated at 60 in the present description. The pressure relief valve 10 can be connected to an externally actuated valve 60 by the connecting element 90 to form the valve assembly 100. The connecting element 90 comprises a main part 50 comprising a first conduit 54a connected to the first reservoir, a second conduit 54b connected to the second reservoir, and comprising a first seat 52 for mounting the valve 10, pressure relief therein and a second slot 56 for retaining it in the valve 60, actuated from the outside (shown in FIG. 5B). The first conduit 54a defines a main hole 58a and a bypass hole 58b, the bypass hole 58b being in fluid communication with the first fluid passage 12a defined by the housing 14 of the pressure relief valve 10. The second conduit 54b is in fluid communication with the second fluid conduit 12b.

An externally actuated valve 60 may be configured to selectively open and close a main opening 58a extending between the first conduit 54a and the second conduit 54b. An externally actuated valve 60 may be configured to be pulsed by a controller (not shown) and thereby allows an intermittent fluid flow to pass through the main hole 58a.

An externally actuated valve 60 may be any valve actuated by an external energy source, as opposed to being actuated by a pressure difference between the first conduit 54a and the second conduit 54b. According to one example of the present invention, the valve 60, actuated from the outside, is an electromechanical valve, in this description is depicted as a solenoid; in alternate embodiments of this example, an externally actuated valve may instead be pneumatically actuated, or any other external energy source.

In the present example, an externally actuated valve 60 comprises a main part 61 of the solenoid containing an armature 62, selectively protruding inward or outward from the main part of the solenoid (not shown). The armature 62 can be deflected by a spring 64 of the solenoid located so that the armature usually protrudes from the main part of the solenoid. The valve 60, actuated from the outside, further comprises a plunger 70 comprising a plunger head 72 and a seal 74 configured to seal contact with the main hole 58a. The plunger 70 is mounted on the armature 62 so that when the latter protrudes from the main part of the solenoid, the plunger head 72 comes into contact with the main hole 58a, preventing the passage of fluid through it.

According to one example, an externally actuated valve 60 is actuated by a controller adapted to receive electric power from a vehicle’s alternator or from any other energy storage device (not shown). The controller may be configured to generate a pulse signal, allowing pulsed actuation of the solenoid, as described in detail below. The controller may be configured to receive an acting signal from a vehicle computer and may comprise a printed circuit board generating an on-demand pulse signal. The valve 60, actuated from the outside, can be designed to normally be in a closed state, and can only be opened in response to actuation by the controller, for example, by an electrical signal.

An externally actuated valve 60 may be perpendicular to the second conduit 54b. Thus, in the case where the second conduit 54b is connected to the outlet for the fuel vapor of the fuel tank, the passage of fluid from the tank forces the plunger head 72 to the main hole 58a, and the pressure inside the tank helps maintain the valve 60, which is actuated from the outside, in the closed position.

The following is a detailed description of an example of the operation of the pressure relief valve 10, as shown in FIG. 2-4, integrated with an externally actuated valve 60 and used inside the steam fuel system and installed in the fuel vapor channel between the fuel tank and the vapor treatment device, hereinafter referred to as the “canister”.

An externally actuated valve 60 may open in response to a signal, such as an electrical signal from a vehicle computer, and a pressure relief valve 10 may open in response to a pressure differential between the sides of the housing 14 exceeding a predetermined differential value. In other words, in the event that the second pipe 54b is connected to the fuel tank and the first pipe 54a is connected to the canister when the pressure in the tank exceeds a predetermined level, the diaphragm element 24 of the pressure relief valve 10 can be opened so as to bring the pressure level in the tank to desired pressure range. Similarly, when the pressure in the tank drops below a predetermined level, the sealing element 26 can be opened so as to bring the pressure level in the tank to the desired pressure range.

In the fully closed position, the externally actuated valve 60 and the opening 18 are closed. In this position, the head of the plunger of the valve 60, externally actuated, engages in sealing contact with the main hole 58a and the diaphragm element 24 is forced forward by the main spring 20 to the sealing element so that the sealing surface 28 abuts the diaphragm element 24, closes the window 25 in it and, therefore, hermetically closes the hole 18.

Thus, in this position, the flow of fuel vapor from the second conduit 54b to the first conduit 54a and therefore from the tank to the canister is prevented. It should be understood that in this position, the plunger 70 operates under the action of the force of the spring 64, forcibly moving the seal 74 on the main hole 58A. Thus, in this position, power from an external source is not needed to power an externally actuated valve 60.

However, in the open position, the externally actuated valve 60 is open while the pressure relief valve 10 remains closed. In this position, the plunger head 72 of the valve 60, externally actuated, comes out of contact with the main hole 58a, thereby allowing vapors to flow from the tank into the canister. The opening of the valve 60, driven from the outside, is carried out in response to a pulse signal from the controller, which, in the case of a solenoid, supplies energy to a coil wound around the main part of the solenoid, thereby causing a pulse displacement of the armature 62 from the main hole 58a. At the end of each pulse, spring 64 forces the armature 62 and plunger 70 to again come into contact with the main hole 58a. Thus, as a result of a pulse signal from the controller, an intermittent fluid flow is generated between the second conduit 54b and the first conduit 54a. Consequently, the vapor stream from the tank to the canister can move in an intermittent manner that does not block the steam fuel valve, which could otherwise become blocked by the upward force, which could otherwise be created by a sudden vapor stream at a high speed.

Accordingly, a pulsed signal can be formed with pulses having a wavelength and amplitude that allow for a measurable pressure relief, and this signal will not lead to breakage of other elements of the steam-fuel system. According to one example, each pulse can last no more than 200 milliseconds and can be repeated 3 or 4 times or more with an interval of at least 200 milliseconds between pulses.

It should be understood that the controller may be configured to provide signals for actuating an externally actuated valve 60 immediately before opening the fuel tank, for example, before refueling it when it is desired to relieve pressure from the fuel tank and balance it with atmospheric pressure. Accordingly, the above-mentioned pulses can be adjusted according to the expected period between confirmation of the need to refuel the tank and the actual opening of the fuel tank. In other words, for example, if the opening of the fuel tank door is used as the initiating factor after which the fuel tank is expected to open, the time interval during which the pressure in the tank must be relieved is the expected time between the opening of the fuel tank door and the actual opening of the fuel tank. According to some examples, the expected time interval is 2 seconds, so the pulse signal is tuned so as to allow substantially depressurizing the tank for 2 seconds.

According to the last example, opening the fuel tank door can automatically send a signal to drive the controller, which in turn generates a pulse signal to control the operation of the solenoid valve 60. It should be understood that other triggering factors can be used to initiate the pulse signal during a predetermined time the interval before opening the fuel tank.

It should also be understood that after depressurizing the fuel tank following the pulse opening of the valve 60, which is actuated externally, the valve can remain open continuously without pulses, for example, to allow refueling of the tank. Thus, it should be understood that the amount of electric power required when generating the pulses may be higher than the amount of energy required to keep the valve 60, actuated from the outside, in a constantly open position. This is because opening the valve 60, actuated externally when the pressure in the fuel tank is high, requires more energy than keeping the valve actuated externally in the open position after depressurizing the tank. Accordingly, the pulse signal initiated by the controller may include pulses having a large voltage amplitude, while the last pulse, after which the valve 60, driven from the outside, remains open, may have a smaller amplitude. This prevents overheating of the valve 60, driven from the outside.

As described above with reference to FIG. 2, the pressure relief valve 10 may open in response to high pressure in the second fluid passage 12b, in the present example, in the second conduit 54b, for example, when the pressure in the fuel tank exceeds a predetermined level. In this position, the forces exerted by the pressure inside the tank overcome the efforts of the main spring 20 by deflecting the piston element 16 and the diaphragm element 24, and forcibly moving the sealing element 26 forward until the lateral protrusion 34 of the levers 32 comes into contact with the side wall 36 at the second edge 22b of the cylindrical wall 22. Since the sealing element 26 is held by the contact of the side wall 36 and the side protrusion 34 of the levers 32, its further forward displacement is prevented. Thus, the sealing surface 28 of the sealing element 26 is out of contact with the diaphragm element 24, thereby allowing the flow of fluid to pass between the second channel 12b for the fluid and the first channel 12a for the fluid through the hole 18. Therefore, the pressure from the tank can be relieved, allowing vapor flow therefrom to pass through the second conduit 54b and the first conduit 54a to the canister.

The diaphragm element 24 (together with the piston element 16) is maintained in a retracted position until the force exerted by the pressure drop on both sides of the hole 18 becomes less than the forces exerted by the main spring 20.

It should be understood that the operation of the pressure relief valve 10 can be configured as an emergency valve to prevent excessive overpressure in the tank that could damage the tank. Thus, under normal conditions, the pressure relief valve 10 remains closed.

Similarly, under normal conditions, the valve 60, actuated from the outside, also remains closed by the efforts of the spring 64, forcibly moving the seal 74 on the main hole 58a. Thus, in the fully closed position, it is not necessary to supply energy from an external source to power the external valve 60, and the pressure relief valve 10 can operate independently, solely in response to the pressure in the tank.

The hole 18 of the pressure relief valve 10 may further open in response to a low pressure in the second pipe 54b, for example, when the pressure in the fuel tank drops below a predetermined level, for example, when a vacuum is created in the tank. In this position, the forces exerted by the pressure inside the tank overcome the forces of the auxiliary spring 30, which biases the sealing element 26 from the hole 18. In this position, the flow of fluid through the hole 18 is facilitated, thereby allowing the vacuum to be released from the tank.

It will be apparent to those skilled in the art to which the subject matter disclosed herein, numerous changes, variations and modifications can be made without departing from the scope of the invention, mutatis mutandis.

Claims (65)

1. A pressure relief valve for controlling fluid flow between a first fluid passage and a second fluid passage, wherein the pressure relief valve comprises: a housing comprising a first part having a first opening associated with said first fluid channel, and a second part having a second opening associated with said second fluid channel, with a mechanical stop being formed in a second housing part; a diaphragm element movably fixed inside the housing and defining a hole for the fluid to selectively provide through it fluid communication between the first channel for the fluid and the second channel for the fluid; moreover, the diaphragm element contains a Central part and a peripheral part, and the diaphragm element is attached inside the specified housing using the specified peripheral part, and moreover, the specified hole for the fluid is located in the specified Central part; a first deflecting element provided in said first fluid channel and configured to forcibly move said diaphragm element to said mechanical stop in a first direction; a piston element located between said first deflecting element and said diaphragm element, said piston element having a lumen exactly corresponding to said fluid opening; and a sealing element provided in said second fluid channel and movably mounted in said housing and comprising a sealing surface configured to reversibly seal said fluid hole, said sealing element comprising a second deflecting element configured to forcibly move said sealing surface to the specified hole for the fluid in the second direction, and the specified sealing element comprises a stop member adapted to limit said movement of said sealing member in said second direction; the specified locking element contains levers passing under the sealing surface and made with the possibility of contact with the wall at the specified end of the housing; moreover, the termination of the contact of the specified sealing surface with the diaphragm element provides: - the passage of fluid flow from the specified first channel for the fluid into the second channel for the fluid through the specified holes for the fluid; - the passage of fluid flow from the specified second channel for the fluid into the first channel for the fluid through the specified holes for the fluid; moreover, the specified mechanical stopper has the shape of a cylindrical wall protruding into the housing from one end of the housing and containing an edge made in such a way as to reversibly abut against said diaphragm element; moreover, the pressure relief valve under normal operating conditions is in the closed position in which: - the specified diaphragm element, when forced forward by the specified first deflecting element, abuts against the specified mechanical stopper; and - the specified sealing element, when forced forward by the specified second deflecting element, provides abutment of the sealing surface in the specified diaphragm element and hermetically closing the specified hole for the fluid; moreover, in response to the excess of the first pressure in the second channel for the fluid of the first predetermined threshold value, the specified diaphragm element is pressed against the specified first deflecting element  and said sealing element is forced to move to said fluid hole and makes sealing contact with it until the locking element restricts its movement, whereby the sealing surface then comes out of contact with said fluid hole, providing fluid communication medium between the second fluid passage and the first fluid passage through said fluid hole, the sealing element being supported in the sealing contact with the diaphragm member via a second deflecting element as long as the movement of said sealing member relative to said housing is stopped said locking element, and in response to a decrease in the second pressure in the second fluid channel below the second predetermined threshold value, said sealing element is pressed against said second deflecting element, while said diaphragm element is pressed against said mechanical stop, whereby said sealing surface comes out of contact with the diaphragm element, providing fluid communication between the first channel for the fluid and the second channel for the fluid through the specified o fluid openings. 2. The valve according to claim 1, characterized in that said first direction is opposite to said second direction. 3. The valve according to claim 1, characterized in that said central part is capable of reversibly moving relative to said peripheral part at least in said first direction. 4. The valve according to any one of paragraphs. 1-3, characterized in that the said sealing element is placed inside the specified cylindrical wall. 5. The valve according to claim 4, characterized in that said cylindrical wall comprises locking elements for restricting the movement of said sealing element in a direction opposite to said second direction. 6. The valve according to any one of paragraphs. 1-3, characterized in that the diaphragm element is able to move in the direction from the sealing element and get out of contact with it after the movement of the specified sealing element relative to the specified housing is stopped by the specified locking element. 7. The valve according to any one of paragraphs. 1-3, characterized in that the said first deflecting element is a first mechanical spring. 8. The valve according to any one of paragraphs. 1-3, characterized in that the said second deflecting element is a second mechanical spring. 9. The valve according to any one of paragraphs. 1-3, characterized in that the said first predetermined threshold value corresponds to the presence of increased pressure in the second channel for the fluid compared with the first channel for the fluid. 10. The valve according to any one of paragraphs. 1-3, characterized in that the specified second predetermined threshold value corresponds to the presence of reduced pressure in the second channel for the fluid compared with the first channel for the fluid. 11. The valve according to any one of paragraphs. 1-3, characterized in that the said first deflecting element, the specified diaphragm element and the specified sealing element are arranged in series and aligned along the axis relative to the specified housing. 12. The valve according to any one of paragraphs. 1-3, characterized in that the said first deflecting element, the specified diaphragm element, the specified sealing element and the specified second deflecting element are arranged in series and aligned along the axis relative to the specified housing. 13. The valve according to any one of paragraphs. 1-3, characterized in that said first deflecting element, said diaphragm element, said sealing element, said second deflecting element and said cylindrical wall are arranged in series and aligned along the axis relative to the specified housing. 14. The valve according to any one of paragraphs. 1-3, characterized in that in response to an increase in pressure in the second fluid channel above a third predetermined threshold value that is less than said first predetermined threshold value, said diaphragm element is pressed against said first deflecting element, and forced movement of said sealing element is supported to the specified hole for the fluid, and the specified third predetermined threshold value is not sufficient to bias the sealing the element so that the locking element restricts its movement, whereby the sealing surface continues to tightly close said fluid hole, interfering with fluid communication between the second fluid channel and the first fluid channel through said fluid hole. 15. The valve according to any one of paragraphs. 1-3, characterized in that said first fluid passage provides fluid communication between the first reservoir and said pressure relief valve, and wherein the second fluid passage provides fluid communication between the pressure relief valve and the second reservoir. 16. The valve according to claim 15, characterized in that said first reservoir comprises a vapor treatment device. 17. The valve of claim 15, wherein said second reservoir comprises a fuel tank. 18. A valve assembly comprising a first pipe connected to a fuel vapor processing device and a second pipe connected to a fuel tank, the valve assembly comprising: pressure relief valve according to any one of paragraphs. 1-3; externally actuated valve; and a connecting element comprising a main part comprising a first pipe connected to a fuel vapor processing device, a second pipe connected to a fuel tank, and comprising a first socket for receiving a pressure relief valve therein and a second socket for holding an external actuated valve therein . 19. The valve assembly of claim 18, wherein said first conduit defines a main orifice and a bypass orifice, wherein said bypass orifice is in fluid communication with a first fluid channel defined by a pressure relief valve body. 20. The valve assembly of claim 18, wherein the second conduit is in fluid communication with the second fluid conduit. 21. The valve assembly according to claim 18, characterized in that the valve, actuated externally, is located in said second fluid channel and is actuated to selectively open or close a fluid connection between the tank and the fuel vapor processing device by means of said main hole. 22. The valve assembly of claim 18, wherein said valve, actuated externally, is configured to be driven by an external energy source. 23. The valve assembly according to claim 22, wherein said valve, actuated externally, is an electromechanical valve. 24. The valve assembly according to claim 23, wherein said valve, actuated externally, comprises a solenoid containing an armature that selectively extends from the main part of the solenoid and slides into it, and a plunger mounted on said armature and configured to creating a sealing contact with the specified main hole. 25. The valve assembly of claim 18, wherein said valve, actuated externally, is a solenoid valve actuated by electricity. 26. The valve assembly of claim 18, wherein said valve, actuated externally, is configured to be pulsed by a controller, thereby allowing an intermittent fluid flow to pass through its main opening located between said first conduit and the specified second pipeline. 27. A pressure relief valve for controlling fluid flow between a first fluid passage and a second fluid passage, wherein the pressure relief valve comprises: a housing comprising a first part having a first opening associated with said first fluid channel, and a second part having a second opening associated with said second fluid channel, with a mechanical stop being formed in a second housing part; a diaphragm element movably fixed inside the housing and defining a hole for the fluid to selectively provide through it fluid communication between the first channel for the fluid and the second channel for the fluid; moreover, the diaphragm element contains a Central part and a peripheral part, and the diaphragm element is attached inside the specified housing using the specified peripheral part, and moreover, the specified hole for the fluid is located in the specified Central part; a first deflecting element provided in said first fluid channel and configured to forcibly move said diaphragm element to said mechanical stop in a first direction; a piston element located between said first deflecting element and said diaphragm element, said piston element having a lumen exactly corresponding to said fluid opening; and a sealing element provided in said second fluid channel and movably mounted in said housing and comprising a sealing surface configured to reversibly seal said fluid hole, said sealing element comprising a second deflecting element configured to forcibly move said sealing surface to the specified hole for the fluid in the second direction, and the specified sealing element comprises a stop member adapted to limit said movement of said sealing member in said second direction; moreover, the termination of the contact of the specified sealing surface with the diaphragm element provides: - the passage of fluid flow from the specified first channel for the fluid into the second channel for the fluid through the specified holes for the fluid; - the passage of fluid flow from the specified second channel for the fluid into the first channel for the fluid through the specified holes for the fluid; moreover, the specified mechanical stopper has the shape of a cylindrical wall protruding into the housing from one end of the housing and containing an edge made in such a way as to reversibly abut against said diaphragm element; moreover, the pressure relief valve under normal operating conditions is in the closed position in which: - the specified diaphragm element, when forced forward by the specified first deflecting element, abuts against the specified mechanical stopper; and - the specified sealing element, when forced forward by the specified second deflecting element, provides abutment of the sealing surface in the specified diaphragm element and hermetically closing the specified hole for the fluid; the specified second channel for the fluid contains an internal channel for the fluid passing through the specified cylindrical wall, and an external channel for the fluid outside the specified cylindrical wall; the specified sealing element is made with the possibility of placement inside the specified cylindrical wall and reciprocating motion relative to the specified cylindrical wall inside the inner channel; moreover, in response to the first pressure in the second fluid channel exceeding the first predetermined threshold value, said diaphragm element is pressed against said first deflecting element and said sealing element is forcedly moved to said fluid hole and comes into sealing contact with it until the locking element does not limit its movement, whereby the sealing surface then comes out of contact with the specified hole for the fluid, providing fluid communication between the specified internal channel of the second fluid channel and the first channel for the fluid through the specified hole for the fluid, and between the specified external channel of the second channel for the fluid and the first channel for the fluid through the specified hole for the fluid, moreover, the sealing element is maintained in sealing contact with the diaphragm element by means of a second deflecting element until the movement of the specified sealing element the nta relative to the specified housing will not be stopped by the specified locking element, and in response to a decrease in the second pressure in the second fluid channel below the second predetermined threshold value, said sealing element is pressed against said second deflecting element, while said diaphragm element is pressed against said mechanical stop, whereby said sealing surface comes out of contact with the diaphragm element, providing fluid communication between the first channel for the fluid and the second channel for the fluid through the specified o fluid openings. 28. The valve of claim 27, wherein said locking element comprises levers extending beneath the sealing surface and configured to contact a wall at said end of the housing.

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